Guard locks are known as part of an access protection device for a closable area of a machine installation which may be the source of a potential hazard. The installation may be, for example, machines or components such as robots for manufacturing, treating or processing workpieces and chemical installations or the like.
A guard lock is arranged between a door or shutter closing the area as movable part and opposing walls or a frame as fixed part. The at least one door or flap, which may be sealed around the periphery and which can be opened and closed by pivoting or sliding, can be arrested or locked by the guard lock.
In each case at least one safety sensor is located between the door and the adjacent wall. In addition, a control is provided which is coupled to the machine installation and the safety sensor in order to enable or disable the guard lock corresponding to the operating state of the machine installation for opening the door. If the machine installation no longer represents a source of a potential hazard for people, i.e. it is possible to reach into the area through the door or to enter the area via the door, by virtue of a standstill state of the movable parts of the machine installation being signalled to the control, for example, by standstill monitors, for example, the control enables the guard locks, with the result that a person can access the area by opening the doors.
If at least parts of the machine installation are not at a standstill or precautions which otherwise need to be taken have not yet been implemented prior to opening of the doors, the guard locks are blocked, with the result that the doors cannot be opened. In addition, the control prevents the machine installation from being brought into operation when at least one door is open.
DE 10 2004 030 362 A1 discloses an apparatus for the controlled locking of a safety-relevant device, such as a safety door or the like, for example. The apparatus has a locking element, which is mounted movably, can be driven by a drive element and can be brought out of a housing of the apparatus into form-locking engagement with the device to be locked for locking purposes.
One disadvantage with the apparatus known from DE 10 2004 030 362 A1 is that, in the event of the locking element being blocked, the drive and/or the locking element can be subject to damage since the locking element and/or the drive can be bent or overheated. The guard lock is then defective and needs to be replaced, which results in downtimes and repair and maintenance work.
The object of the invention is therefore to provide a guard lock for a component for closing an opening in accordance with the preamble of claim 1, with which guard lock a simple configuration of an improved and safe guard lock is possible, in which damage to the guard lock can be prevented with simple means.